0422 - Hormones and Cancer

Question 1

What are some hormone-related cancers?

Answer 1

Breast
Prostate
Uterine (endometrial)
Ovarian
Thyroid

Question 2

Which hormone is most closely related to increasing breast cancer risk?

Answer 2

Oestregon.

Question 3

How can you predict whether a patient will respond to endocrine therapy for breast cancer?

Answer 3

ER/PgR positivity (75% are HR positive)
Long Disease-free interval (diagnosis to metastasis)
Mets to bone and soft tissue instead of viscera

Question 4

What are some drugs that are used as endocrine therapy for breast cancer?

Answer 4

Tamoxifen (oestrogen receptor antagonist) - mostly for premenopausal women.
Aromatase inhibitors - even better, but only for postmenopausal (premenopausal contradicted)
Ovarian function suppression (premenopausal only) - LHRH agonists, stimulate for 24 hours then ‘overload’ and stop LH release, silencing ovaries.

Question 5

Briefly outline tamoxifen

Answer 5

Non-steroidal antioestrogen - binds to ER which translocates to nucleus and thus unable to receive oestrogen.
Given orally
Oestrogen antagonist, BUT partial agonist in bone, blood, and endometrium.
Effective in pre- and postmenopausal women.
Well tolerated, but increase risk of thromboembolism and endometrial cancer

Question 6

How do aromatase inhibitors work?

Answer 6

Prevent peripheral conversion of androstenedione to oestrone or testosterone to oestradiol
Aromatase in breast tumour, muscle, fat, skin, liver
Thus reduce circulating oestrogens which could stimulate tumour growth.

Question 7

What are three aromatase inhibitors?

Answer 7

Anastrozole, Letrozole (non-steroidal)

Exemestane (steroidal)